Images produced for broadcast in movie studios or broadcasting stations have a narrow color gamut optimized for a sRGB panel corresponding to the BT 709 standard. On the other hand, with the recent development of IT technology, demand of users for higher quality images are increasing. Accordingly, research into techniques for expanding a color gamut of an image has been actively conducted.
However, the existing technology has a problem in that distortion occurs in color conversion due to the color gamut of the image expanding all at once or mapping of a color of the image based on a fixed mapping table to expand the color gamut. Therefore, it is necessary to develop a technique for minimizing color distortion while expanding the color gamut of the image.